Have you ever spent hours working on a hair to end up with something like this?

No worries! I’ll teach you to get rid of those annoying problems!

NOTE: This tutorial won’t work if your mesh is not separated in groups. If you didn’t save a copy of a non-regrouped mesh or didn’t change the group names on SimPE (when all the groups have the same name, SimPE regroups them while exporting), you’ll have to start all over again. Sorry!

1st Step ~ Recognizing the transparency issues
It’s very easy. First of all, you have to assign your mesh to a material, and make sure “Draw backfaces” and “Transparency>Depth Buffered with Alpha Reference” are activated.
Now, if you go around your mesh, you’ll probably notice something like this:

You’ll probably find blue lines (or whatever background color you’re using) and “ghost” groups (you can see trough them), those are the transparency issues you can see in-game.

2nd Step ~ Fixing the transparency issues – part 1
The technique it’s very easy, but sometimes it can takes a very long time.
All you have to do is, first, recognize the group you’re trying to fix, select it in “Groups” tab, and then press the button that says “Down”. Now click the 3D viewport. If it didn’t change, keep moving it until you see the difference.

If it looks all smooth like this, then the group it’s located in the right position.

Note: When higher it’s the piece of hair in the mesh, lower should be it group on the “Groups” tab. For example: strands coming out from the hairline and that are over all the rest of the hair, should be at the bottom of the “Group” tab.

Note 2: Sometimes you need to separate a group to the fix the transparency issue. For example: you have a strand at the top of the hair that doesn’t have issues and, in the same group, another strand that it’s somewhere else and it does have issues, you’ll probably need to separate them, so you can locate both in their right places.

3rd Step ~ Merging normal’s dataNote: Do this step once you’re done with the hair and you saved your work!
Select all the groups, and go to “Vertex>Sims2 UniMesh Normal Data Merge V4.09”.

Your mesh has gone all black and wonky, so (in the same menu) use “Align Normals”. This way you can regroup everything without losing all your work with the transparency issues. This is VERY IMPORTANT! So make sure you did it!

4th Step ~ Fixing the transparency issues – part 2
Now you’re almost done, but you have to know that the undersides can ruin your hair as well. So, after you did them (Duplicate group, Reverse Vertex Order, Scale all by .999, Align normals), move the undersides up in the “Groups” tab, and click on the 3D viewport. You’ll notice that more transparency issues have been murdered.

At last, select the undersides if not selected, “Vertex>Sims2 UniMesh Normal Data Merge V4.09”, “Align Normals” , regroup and… your mesh is done! Note: Don’t forget to import the comments, assign bones to the mesh and use the Extra Data Tool before exporting!

5th Step ~ Test, test and test
This is how it should look now:

Test the hair very carefully, make sure that you’ve fixed everything. If not, open your saved non-regrouped file (that I told you to save in step 3) and work with.

Feel free to ask anything you want.

I hope this helps! ^-^

Special thanks to Cazy and Savio for teaching me this. You're awesome, guys!

Have you ever spent hours working on a hair to end up with something like this?

No worries! I’ll teach you to get rid of those annoying problems!

NOTE: This tutorial won’t work if your mesh is not separated in groups. If you didn’t save a copy of a non-regrouped mesh or didn’t change the group names on SimPE (when all the groups have the same name, SimPE regroups them while exporting), you’ll have to start all over again. Sorry!

1st Step ~ Recognizing the transparency issues
It’s very easy. First of all, you have to assign your mesh to a material, and make sure “Draw backfaces” and “Transparency>Depth Buffered with Alpha Reference” are activated.
Now, if you go around your mesh, you’ll probably notice something like this:

You’ll probably find blue lines (or whatever background color you’re using) and “ghost” groups (you can see trough them), those are the transparency issues you can see in-game.

2nd Step ~ Fixing the transparency issues – part 1
The technique it’s very easy, but sometimes it can takes a very long time.
All you have to do is, first, recognize the group you’re trying to fix, select it in “Groups” tab, and then press the button that says “Down”. Now click the 3D viewport. If it didn’t change, keep moving it until you see the difference.

If it looks all smooth like this, then the group it’s located in the right position.

Note: When higher it’s the piece of hair in the mesh, lower should be it group on the “Groups” tab. For example: strands coming out from the hairline and that are over all the rest of the hair, should be at the bottom of the “Group” tab.

Note 2: Sometimes you need to separate a group to the fix the transparency issue. For example: you have a strand at the top of the hair that doesn’t have issues and, in the same group, another strand that it’s somewhere else and it does have issues, you’ll probably need to separate them, so you can locate both in their right places.

3rd Step ~ Merging normal’s dataNote: Do this step once you’re done with the hair and you saved your work!
Select all the groups, and go to “Vertex>Sims2 UniMesh Normal Data Merge V4.09”.

Your mesh has gone all black and wonky, so (in the same menu) use “Align Normals”. This way you can regroup everything without losing all your work with the transparency issues. This is VERY IMPORTANT! So make sure you did it!

4th Step ~ Fixing the transparency issues – part 2
Now you’re almost done, but you have to know that the undersides can ruin your hair as well. So, after you did them (Duplicate group, Reverse Vertex Order, Scale all by .999, Align normals), move the undersides up in the “Groups” tab, and click on the 3D viewport. You’ll notice that more transparency issues have been murdered.

At last, select the undersides if not selected, “Vertex>Sims2 UniMesh Normal Data Merge V4.09”, “Align Normals” , regroup and… your mesh is done! Note: Don’t forget to import the comments, assign bones to the mesh and use the Extra Data Tool before exporting!

5th Step ~ Test, test and test
This is how it should look now:

Test the hair very carefully, make sure that you’ve fixed everything. If not, open your saved non-regrouped file (that I told you to save in step 3) and work with.

Feel free to ask anything you want.

I hope this helps! ^-^

Special thanks to Cazy and Savio for teaching me this. You're awesome, guys!

How do we get the different groups before we export? I'm not converting meshes and that's what SimPE says its for. I use S3PE. How do we get the different groups from there?

How do we get the different groups before we export? I'm not converting meshes and that's what SimPE says its for. I use S3PE. How do we get the different groups from there?

This might be a bit of a necro-bump, but I wanted to share. First off, you need a 3D application, SimPE is not a 3D app. As you create the hair using hair planes in your 3D app, you should be grouping them separately (each plane is an individual element). If you didn't do this, you can go into 3DS Max and separate the elements easily by hand into different objects or use the Detach Elements script at ScriptSpot. By assigning the diffuse and alpha maps and rendering them in the viewport, you can easily detect which element is the problem. Then attach them one by one.

If you don't have Max, Blender has a similar feature discussed in this thread. Basically, select a part of the mesh and then press "ctrl" and "+" to select connected adjacent faces (elements) or "L" to select adjacent vertices. You can then split them into separate objects and continue on with the tutorial.

This issue persists whenever planes with transparency information overlap. It has to do with the sorting order, usually the last plane added will go over the first plane.

✦ A Psycho'sTrip ✦ Stay in Wonderland and I'll show you how deep the rabbit hole goes